<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>AMD</title>
</head>
<body>
    <script src="https://unpkg.com/requirejs@2.3.6/require.js"></script>
    <script>
        //通过使用require方法异步加载和使用
        require(['umd'],function(umd){
            console.log(umd.sum(1,2))
        })
    </script>
</body>
</html>